1. Field of the Invention
The present invention is concerned with the presence of alkanesulfonates in a toilet detergent tablet having an acyl isethionate as the predominant surface active detergent, to lessen the tendency of the tablet to form mush in the holder.
It is well known that toilet tablets, both those based on soap and on nonsoap synthetic detergents, hydrate or absorb water, when left wet in the conventional holder, or dish, after using. The hydrate is soft, and this condition may exist not only on the surface but for some distance below the surface. The hydrate falls from the tablet, or is removed during the next usage, depending upon the degree of softness. This softening and removal is variously referred to as sliming, sloughing, melting, slushing, smearing, slopping, mushing, etc.
Various additives have been incorporated in soap and detergent tablets to ameliorate mushing tendencies, as set forth elsewhere herein. However, it is believed that the anti-mushing agents of the present invention have particular adaptability to nonsoap detergent toilet tablets wherein an acyl isethionate is the predominant surface-active agent.
2. The Prior Art
U.S. Pat. No. 2,197,800 discloses a process for reacting a paraffinic hydrocarbon with a gaseous mixture of sulfur dioxide and chlorine.
U.S. Pat. No. 3,001,948 relates to a synthetic detergent bar consisting essentially of an ammonium alkanesulfonate admixed with an alkali metal or alkaline earth alkanesulfonates, the alkane portion being primary straight chain radicals having 8-20 carbon atoms and averaging 12-16 carbon atoms.
U.S. Pat. No. 3,186,948 discloses a 1:1 mixture of alkanesulfonate and secondary alkyl sulfate.
U.S. Pat. Nos. 3,228,980 and 3,297,579 disclose alkanesulfonates having an odd number of carbon atoms, and a process for their preparation.
U.S. Pat. No. 3,533,954 relates to washing powders consisting essentially of a soap and an aliphatic alpha sulfonate.
U.S. Pat. No. 3,541,140 describes a method for preparing sodium alkanesulfonates.
U.S. Pat. No. 3,652,662 discloses the use of hydrogenated olefin sulfonates in bar form.
The procedures for preparing alkali metal acyl isethionates are well known to those skilled in the art. The reaction between isethionic acid free of its salts, and fatty acids is described in U.S. Pat. No. 3,151,136. The acid reaction product is neutralized preferably with a mixture of sodium hydroxide and sodium disilicate. U.S. Pat. No. 3,320,292 discloses the use of a basic zinc compound as a catalyst in the preparation of an acyl isethionate from a fatty acid and sodium isethionate, while U.S. Pat. No. 3,383,396 discloses the use of a zirconium compound in the same preparation. The basic bar composition is described in U.S. Pat. No. 2,894,912. U.S. Pat. Nos. 3,420,857 and 3,420,858 disclose processes for controlling the distribution of the several chain-length fatty acids used in the admixture in the preparation of acyl isethionates. U.S. Pat. No. 3,429,136 discloses a step of flash-cooling acyl isethionates after preparation